Code A048: Excessive Right Front Wheel Speed Acceleration

1990 Buick Regal Custom, 3.8 L, 4T60/ME9SECTION Code A048: Excessive Right Front Wheel Speed Acceleration

Wheel sensors generate voltage signals as the wheel rotates. The created frequency enables the anti-lock brake controller to determine wheel RPM. If the information received is not within preset values, the anti-lock brake controller determines signal is faulty and set Code A048. To set Code A048, the following conditions must occur.

  • Brakes are not applied (brake switch off).
  • Anti-lock brake controller senses illogical right front wheel speeds.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Observe right front wheel speed input to determine what type of input the anti-lock brake controller is sensing. Erratic or unsteady readings indicate a malfunction in wheel speed sensor. Stable readings indicate problem is intermittent.
  2. Indicates wheel speed sensor has internal short to ground.
  3. If resistance is infinite, wheel speed sensor has internal open condition.
  4. Circuit No. 833 is connected to ground. If infinite resistance is measured, an open condition is present in circuit No. 833.
  5. Circuit No. 872 is connected to ground. If infinite resistance is measured, an open condition is present in circuit No. 872.
  6. All systems that can be checked have tested good. Visually inspect speed sensor, speed ring wire harness and all connectors. Check component mounting and alignment. If problem persists but source cannot be found, replace anti-lock brake controller.
NOTE: INTERMITTENTSΒ  is located under DIAGNOSIS & TESTING.
RENDER: 1.0x

NO RELATED

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